The present invention relates to a structural casing for supporting rotating parts of a turbine engine, in particular of a turbojet.
As illustrated in FIG. 1, a turbine engine 1 generally comprises a tubular enclosure 2, containing rotating bodies, such as compressor stages 3-4 and turbine stages 5-6, mounted on one or more rotating shafts 7 arranged axially in the enclosure 2 of the turbine engine, which constitutes a stator.
The structure of a turbine engine 1 includes structural casings 8 and 9 which support the shaft or shafts 7 in rotation. These casings are connected to the aircraft via suspension parts (pylon, strut, attachments or links).
A turbine engine 1 includes at least two structural casings 8 and 9: an intermediate casing which supports rotation bearings at the front of the rotating shaft 7 and an exhaust casing 9 which supports rotation bearings at the rear of the rotating shaft 7.
The casings 8 and 9 have the function of suspending the rotating bodies 3 to 7 of the engine in the stator 2, of immobilizing the rotation bearings and of transmitting the mechanical loads of the bearings toward the stator 2.
Documents FR-A-2 641 328, FR -A-2 681 401 and JP-A-9-324 699 show examples of structures of turbine engine casings.
As illustrated in FIG. 2, a structural turbine engine casing 9 of known type comprises a central hub 10 serving as a bearing support, an intermediate annular shroud 20 and an external ring 30, which are concentric to the central hub 10. The central hub 10 and the intermediate shroud 20 are connected fixedly and rigidly by a series of multiple arms 11 to 19 (numbering nine here) arranged radially. The intermediate shroud 20 and the external ring 30 are connected in an articulated manner by means of suspension links 22. These links 22 serve to transmit the mechanical loads (landings, steering maneuvers, thrust, engine unbalance) between the hub 10, the arms 11-19, the intermediate annular part 20 and the external annular part 30. The structural arms 11-19 have a profiled hollow structure which is dimensioned to withstand these mechanical loads.
The disadvantage is that the dimensioning of the hollow arms of the known structural casings does not allow them to withstand large mechanical loads over a prolonged period.
However, a constant objective in aeronautics is to reduce the mass of the component parts of aircraft without harming their performance.